pH storage solution alternative

bearpaw8491 · Sep 28, 2022

Local wine supply shop was out of pH probe storage solution when I stopped by yesterday. Westlabs indicates that if 4M potassium chloride solution isn’t available, it’s acceptable to store probe in either pH 4 or 7 buffer solution.

Does anyone do this on a regular basis? Would be great to find another use for the buffer solution(s) ( I use sachets) after calibration rather than tossing.

Cynewulf · Sep 28, 2022

I used pH 4 buffer to store my probe for about a year until I got some electrode storage solution. It seems to be ok.

bearpaw8491 · Sep 29, 2022

Thanks Erik

, will follow your lead until my local brew shop is restocked.

rsportsman · Sep 29, 2022

I would use pH 4 buffer in a pinch, but prolonged storage in that buffer can deplete the reference electrode's buffer, leading to errors. So get replacement storage solution as soon as possible. Vinmetrica uses essentially 2M potassium chloride in pH 4 reference solution and it is available from us.

BTW, most pH electrodes, like Vinmetrica's, are OK stored dry! Way better in fact than in water or pH 7 for prolonged storage. You do have to re-hydrate them for a few hours in fresh storage solution before using them again.
-Rich at Vinmetrica

Cynewulf · Sep 29, 2022

Heh, I would definitely follow Rich’s lead, rather than mine! Just sharing what I did when I was too absentminded to order the proper electrode storage solution. I also meant to add that some odd black stuff seemed to grow when I stored the bulb in the 4.0 buffer solution, but has stopped since I switched to the correct storage solution.